City of the Dead, Cairo, Egypt. The City of the Dead is a large area just east of downtown Cairo containing tombs with graves, some dating back 1000 years. The custom was that more affluent families would build more intricate tombs for the family, with other tombs being simpler. A living area would normally exist within the tomb area where people could live while tending the graves. As time went on, many tombs were either abandoned, or the families moved away, or passed away, leaving thousands of tomb living areas empty. Due to the population explosion and cost of living, many people moved into the tombs to live starting in the 1960's. Currently the number of people living there is unknown, but estimates are that it is in the mid 100,000's. Photo by Wally Nell/ZUMA Press